1. Technical Field
The present invention relates to a circuit device, an oscillation device, an electronic apparatus, and so on.
2. Related Art
In the past, there has been known a temperature compensated quartz crystal oscillator (TCXO). The TCXO is used as a reference signal source or the like of an RF circuit of a wire-less device such as a portable terminal. As related art of the circuit device for realizing the TCXO, there can be cited a technology disclosed in, for example, JP-A-2009-124214 (Document 1).
Incidentally, in an resonator such as a quartz crystal resonator, if the resonator is used in the state in which a foreign matter generated in the manufacturing process is attached to the resonator, there arise a problem, for example, that the oscillation frequency becomes unstable due to the foreign matter, and a problem that the oscillation frequency jumps to a different frequency if the foreign matter attached thereto is detached.
In this case, it is possible to adopt a method of performing overdrive (strong excitation) on the resonator as a unit prior to installing the resonator in the oscillation device to thereby remove the foreign matter.
However, depending on the package structure of the oscillation devices, there are some oscillation devices having a structure difficult to perform such an overdrive test on the unit resonator. Further, even if the package structure of the oscillation device is the structure allowing the overdrive test, there is a problem that it is difficult to provide overdriving electrodes (terminals) due to miniaturization of the package of the oscillation device and the circuit device (IC) incorporated therein.